This invention relates to a rate control system in a system where it is desirable to control the rate of units of work per measure of time. More specifically, the invention is related to a demand driven model that performs a simple and precise scheduling computation for each service request.
Token bucket algorithms are metering engines that keep track of how much traffic can be sent to conform to specified traffic rates. A token, or in some cases a quantity of tokens, permits the algorithm to process a request. Tokens are granted at the beginning of a time increment according to a specified rate. Token buckets may be applied to resources of a network that are shared by multiple network devices, such as switches, routers, etc., where they are used to control data flow between network devices. Specifically, the token bucket employs credits in the form of tokens with the credits generally correlated to bandwidth.